In multi-device or multi-user equipment communication systems, messages may be broadcast to multiple devices or UEs over a shared channel. All UEs typically receive the same data over a shared channel, such that, a message intended for one or more UEs (e.g., referred to as a UE-specific or UES message) is received by all connected UEs. Each UE extracts from the shared data only UES messages that are directed to that UE and disregards messages that are not directed to that UE. Modern examples of multi-user cellular communication standards include Long-Term Evolution (LTE) and 3rd Generation Partnership Project-New Radio (3GPP-NR).
To distinguish the intended recipient of UES messages over a shared channel, each UE or set of UEs may be uniquely identified by a user equipment identification number (UEID) and each UES message may include the UEID of the target UE to identify the intended recipient(s). If a UE receives a candidate UES message that ultimately turns out not to be allocated to that UE (e.g., either because the UES message is allocated to another target UE, or due to lack of transmission), the UE should identify this as early as possible and terminate the decoding process to minimize wasted computational resources. Terminating decoding the UES message prior to its completion is referred to as “early termination” or “ET.”
Early Termination typically improves UE performance by decreasing decoding latency and power consumption, e.g., eliminating or cutting short decoding attempts of candidate messages that are “false” (not intended for the UE). A disadvantage of ET is that it may lead to false negatives, in which a “true” candidate message (intended for the UE) is wrongly identified by the UE as a false candidate in an earlier decoding stage, whereas the message would have been revealed in a later decoding stage to be a true candidate message if decoding had continued. In such cases, early termination may degrade the accuracy or block error rate (BLER) performance of the decoder. Conversely, the ET may encounter false positives, in which the UE wastes resources decoding false candidate message (not intended for the UE) that are incorrectly identified by the UE as a true candidate.
In conventional ET, the target UEID is typically added as a field in the message header. To determine if a “candidate” UES message is allocated to a particular UE, the UE must usually decode the entire message because the header and message are typically encoded together by the same ECC redundancy. In cases where the header and message are encoded separately, separate ECC redundancy must be transmitted for the header and message body and an additional encoding step is needed to separately decode the header, delaying decoding of the message body. Further, attaching the target device identifier to the message header or body increases the message size and requires additional bandwidth and increases latency.
Accordingly, there is therefore a need in the art of multi-user communication systems to improve the speed and accuracy of ET decisions and decoding UES messages.